The invention provides a method for preparing 3,4-dihydro(2H)-1,5-benzodioxepin-3-ones represented by the formula (3):
wherein R1, R2, R3 and R4 respectively represent, independently, a hydrogen atom an alkyl group or an alkenyl group, and R1, R2, R3 and R4 as a whole do not comprise more than 10 carbon atoms and that, when the two adjacent groups respectively comprise an alkyl group or an alkenyl group, they may be combined together to form a carbon ring; by reacting either a compound represented by the formula (1a) and/or (1b):
wherein X represent a halogen atom; and R1, R2, R3 and R4 are as defined above; or catechols represented by the formula (5):
wherein R1, R2, R3 and R4 are as defined above;
with 1,3-dihaloacetones in the presence of sodium carbonate, through the removal of hydrogen halide.
该发明提供了一种制备3,4-二
氢(2H)-1,5-
苯并二噁
呋喃-3-
酮的方法,其表示为公式(3):其中R1、R2、R3和R4分别独立地代表
氢原子、烷基或
烯基,且R1、R2、R3和R4作为一个整体不含有超过10个
碳原子,并且当两个相邻的基分别包含烷基或
烯基时,它们可以结合在一起形成一个
碳环;通过在
碳酸钠存在下,通过去除
氢卤化物来反应公式(1a)和/或(1b)所代表的化合物:其中X代表卤素原子;R1、R2、R3和R4如上所述;或者用公式(5)所代表的
邻苯二酚:其中R1、R2、R3和R4如上所述;与1,3-二卤代乙
酮反应。